Properties of Matter: Investigation 1 –
Properties of Matter: Investigation 1
Note: During the course of this Concept Day presentation, we wish to establish the definition of matter and the relationship between matter, elements, atoms, molecules, and compounds. This hierarchy sometimes confuses students at first.
- Matter is anything that takes up space (has volume) and has mass.
- Matter is composed of elements.
- There are 118 elements
- Atoms are the smallest particle that an element can be broken down to and still have all the characteristics and properties of that element.
- Molecules are what you get when two or more atoms combine. This might be two or more of the same element like H2, O2, or a pure metal (Au, Ag, Cu).
- A compound is a molecule that simply contains more than one kind of atom.
- Everything, EVERYWHERE that has volume and mass is composed of matter.
Note: The brass weights at the bottom are masses you will be familiar with in LabLearner by grade 6.
- As we move from the entire Earth into the solar system and the whole Universe, everything is composed of matter.
- Human beings are also 100% composed of matter.
- Can you suggest other things made of matter.
Read the terms on the slide.
Note: Do not worry about the layout or details of the Periodic Table. For now, think of it as simply a chart of the known elements.
- Several of the elements you may have heard of before.
- You will come in contact with some of the elements in the Periodic Table elements in Lab such as copper, aluminum, and calcium.
Note: The table below is for your reference. These are all elements you may already be familiar with.
- Elements, such as oxygen, are composed of smaller, subatomic particles called protons, neutrons, and electrons.
Note: Every atom contains a “nucleus” containing the same number of protons and neutrons in most cases. These are surrounded by a cloud of electrons that are present in the same number as protons.
Note: The number of protons gives us the atomic number on the Periodic Table of the Elements – there are 8 in the case of oxygen. Also, notice that the number of protons plus electrons gives us the approximate “molecular weight” of the element that is shown below its symbol on the Periodic Table.
- Notice in this slide, two atoms of oxygen are needed to build one oxygen molecule (O2).
- This slide also depicts a compound (H2O) to demonstrate the difference between a molecule and a compound.
Note: A compound is also a molecule, but a special class because it is composed of more than one kind of element. Many, many molecules in the Universe are compounds.
Note: You will examine various compounds in the lab throughout this CELL. In Investigation 1, you will be asked to examine samples and record observations about their physical characteristics.
- The definition of a physical property and some examples are listed on the left.
- There are other physical properties not listed here, but these are common.
- The cube on the right is shown with a few physical properties one might use to describe it (color, texture, and size).
Note: Physical properties are typically adjectives. In lab, make sure to include as many adjectives as possible to describe your unknown samples. This is not only good practice for developing scientific observational skills, but also for your descriptive vocabulary use as well!
- Note: This slide simply illustrates a triple beam balance that will be used in the lab as a refresher. Grade 6 LabLearner students will be familiar with this instrument.
- Remember that we measure and report mass using a triple beam balance.
- Remember that we measure and report mass in metric units of grams.
- Review the mathematical formula and volume displacement methods of determining volume.
- You will use both methods in this Investigation.
- Note: The volume displacement method is shown in the Prelab video, but take time to be sure you understand the concept here.
Note: You may be familiar with the concept of volume displacement by seeing the water level rise as you step into a bathtub or put too many ice cubes in a soft drink, causing it to overflow!